Changing variable types in Python Pro Preview

In this tutorial, you will learn how to change a variable from one type to another in Python. This process is called casting. It is especially useful when you need to convert numbers into text (strings) so they can be printed inside messages or displayed to users.

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  • #2599
  • 12 Mar 2026

In Python, variables can store different types of data. For example:

  • Integers (int) – whole numbers such as 5 or 42

  • Strings (str) – text such as "Hello" or "Score"

Sometimes, you need to convert one type into another. This process is called casting.

To convert a number into text, you use the str() function.

Example:

from hub import light_matrix
import runloop

score = 10

async def main():
    # Display the score
    message = str(score)
    light_matrix.write(message)

runloop.run(main())

Here is what happens:

  • score stores the number 10

  • str(score) converts that number into the text "10"

  • The variable "message" now stores a string instead of a number

Even though it still looks like 10, Python now treats it as text.

You can also use str() directly inside the brackets.

Example:

from hub import light_matrix
import runloop

score = 10

async def main():
    # Display the score
    light_matrix.write(str(score))

runloop.run(main())

Courses and lessons with this Tutorial

This Tutorial is used in the following courses and lessons

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